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Background Different red winemaking were carried out to evaluate the effects of the prefermentative addition of chitosan, as an alternative to the use of SO2 , on the secondary products of alcoholic fermentation, yeast available nitrogen (YAN), biogenic amines and ethyl carbamate. Results The wines made with chitosan presented higher total acidity and higher content of tartaric and succinic acids than those made only with SO2 . The use of chitosan in winemaking resulted in wines with higher glycerol and diacetyl content without increasing the concentration of ethanol, acetic acid, acetaldehyde or butanediol. YAN was lower in wines made with chitosan, which may mean an advantage for the microbial stability of the wines. Furthermore, the use of chitosan at the beginning of alcoholic fermentation did not increase the concentration of biogenic amines or the formation of ethyl carbamate in SO2 -free red wines. Conclusion The total or partial substitution of SO2 for chitosan at the beginning of the alcoholic fermentation gives rise to quality red wines without negatively affecting their nitrogen fraction or their very important secondary fermentation products such as acetic acid or acetaldehyde. © 2020 Society of Chemical Industry.

The aim of this work was to research the relationship between volatile composition of Petit Verdot red wines and the fermentation temperature. Winemaking process was carried out at 17 °C, 21 °C, and 25 °C temperatures. Solid-phase extraction (SPE) and gas chromatography–mass spectrometry (GC–MS) were used to analyse volatile compounds. The odour activity values (OAVs) from the different compounds were classified into seven odorant series that describe the aroma profile (fruity, floral, green/fresh, sweet, spicy, fatty, and other odours). The value of each aromatic series was obtained by adding the OAVs of the volatile compounds to each series. The volatile composition was significantly affected by the temperature of the fermentation. In general, the increase in the fermentation temperature of La Mancha Petit Verdot red wines from 17 to 25 °C produced an increase in the concentration of volatile aroma compounds. The highest aroma contributions to Petit Verdot wine were fruity, sweet and floral series, followed by fatty and spicy series, regardless of fermentation temperature. The highest values of aromatic series were found in wines fermented at 21 °C. The results of this work show that changes in the fermentation temperature of wines can have a significant impact on their volatile compound profile.

The detailed phenolic composition of different berry parts from two novel V. vinifera L. red grape genotypes (Moribel and Tinto Fragoso), together the well-known Tempranillo, was established using high performance liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) over two consecutive vintages (2016 and 2017). More than 50 phenolic compounds were identified and quantified: 25 anthocyanins, 17 flavonols, 7 hydroxycinnamic acid derivatives, 2 stilbenes, and several flavan-3-ols. As far as we know, some anthocyanin and flavonol dihexosides were reported for the first time in V. vinifera L. grapes. Application of Principal Component Analysis (PCA) to experimental data showed a good separation of the novel grape genotypes and Tempranillo according to the phenolic profile of skins and seeds, mainly based on the proportion of trisubstituted anthocyanin derivatives, flavonols and flavan-3-ols, being a useful tool to differentiate these grape varieties.

The chemical oxidation of white wines through the Fenton reaction has been widely studied, wherein the primary species is the hydroxyl radical ( OH). This radical possesses high oxidising power and may oxidise the primary components in wines. The Fenton reaction in wines is complex and includes the participation of phenolic compounds, organic acids, and metals. However, there has been no systematic study to date that relates wine composition to OH production in real white wines. In this paper, a multivariate model was generated using the partial least squares (PLS) algorithm, and linear correlations were established between wine composition and OH production. Based on the results, the variables were classified as either pro-oxidants (malic acid, p-coumaric acid, and caffeic acid, % prodelphinidins, procyanidins B1, Mn, Cu, and Zn) or antioxidants (cis-piceid, ellagic acid, gallic acid, proanthocyanins, glucose, and proton concentration). Finally, the pathways by which wine compounds participate in OH production are discussed.

The ability to obtain different wines with a singular organoleptic profile is one of the main factors for the wine industry’s growth, in order to appeal to a broad cross section of consumers. Due to this, white wines made from the novel grape genotypes Albillo Dorado and Montonera del Casar (Vitis vinifera L.) were studied and compared to the well-known Airén at two consecutive years. Wines were evaluated by physicochemical, spectrophotometric, high-performance liquid chromatography–diode array detection–mass spectrometry, gas chromatography–mass spectrometry and sensory analyses. The chromatic characteristics of the new wines were defined by more color purity than Airén, with greenish highlights. In general, the phenolic profile of the Albillo Dorado wines showed a higher flavonol and hydroxycinnamic acid derivative content. Several volatile compounds were determined, and their odor activity values were calculated to determine their impact on wine aroma. A fruity series dominated the wine aromatic composition, but spicier and greener notes characterized the aroma profile of Airén wines. Albillo Dorado and Montonera del Casar were sensory evaluated as wines with a less fresh taste compared to Airén. Unique chemical and sensory profiles were determined for wines made from these novel grape genotypes, providing alternative monovarietal wines to encourage the wine market growth and extend the offer to consumers.

Due to the current dominance of a few grape varieties in the wine market, the aim of this work was to study the detailed phenolic and volatile composition, chromatic characteristics, and sensorial properties of red wines elaborated with new Vitis vinifera grapes (Moribel and Tinto Fragoso) identified using the High Perfomance Liquid Chromatography-Diode Array Detector-Electrospray Ionization-Tandem Mass Spectrometry (HPLC-DAD-ESI-MS/MS), Gas Chromatography- Mass Spectrometry (GC-MS), CIELab color space, and Napping ? techniques. RESULTS Tinto Fragoso wine showed higher phenolic content than Moribel, with more anthocyanins, flavonols, and stilbenes. These wines also contained anthocyanin diglucosides not reported for Vitis vinifera wines. The odor activity values of free volatile compounds were calculated to indicate their influence on wine aroma, the fruity aromas of Moribel standing out particularly. The wines studied were positively evaluated by the tasters. Moribel's sensory profile was characterized by red fruit aromas and Tinto Fragoso showed more aromatic intensity and persistence in the mouth. CONCLUSION The results obtained from the first characterization of red wines made from novel Vitis vinifera grapes suggest that Moribel and Tinto Fragoso could be appropriate raw materials for the elaboration of quality young red wines. Tinto Fragoso provided wines with sensorial properties different from those of Tempranillo, and could be an alternative to the well known red wines on the market. ? 2018 Society of Chemical Industry

For the first time vine-shoot tannin composition was carried out by means of HPLC-DAD-ESI-MS/MS. Two vine-shoot cultivars (Airén and Cencibel) with different post-pruning storage times were submitted to a toasting process and assayed. There were no traces of gallotannins nor ellagitannins, but a high proanthocyanidin content and a mean degree of polymerization (mDP) close to 3 were characterized. The higher concentration of proanthocyanidins corresponded to Airén after 6 months post-pruning storage and at 3 months for Cencibel. Procyanidins were the most abundant fraction (70-95%), which decreased with storage, and especially significant was the contribution of B1, B2, and B4 dimers. Prodelphinidins were also found (8-24%), increasing their % with storage time. Toasting produced a considerable reduction of proanthocyanidin content and a loss of a monomer mDP unit, suggesting that if used as oenological tannins, then they may be more bitter and less astringent when compared with the nontoasted vine-shoot samples.

The purpose of this work was to study the possibility of partially or totally replacing the use of SO2 during white wine elaboration by using saturation of grape musts with CO2 at the prefermentative stage. No differences were observed in main oenological parameters between wines from musts with and without CO2. Wines from musts with and without CO2 were submitted to an accelerated oxidation test that showed small changes in their browning capacity, without technological significance. Regarding volatile composition, the saturation of must with CO2 and the corresponding SO2 dose reduction resulted in fruit- and floral-driven wines that contribute most to the aromatic character of white wines. The sensory analysis of wines was carried out by Napping®, showing results in accordance with the volatile composition. After 12 months of bottling, wines were stable against acetic bacteria but the absence of SO2 led to the development of malolactic fermentation in the bottle. On the basis of the current study's results, it could be suggested that this technique may be a feasible alternative that contributes to the reduction of the use SO2 doses in wines, achieving stable wines over 12 months and showing a distinctive aromatic profile.

This work studies the influence of two different nitrogen sources added to the must on aromatic series and sensory profile of ‘Chardonnay’ wines. Volatile compounds were classified into six odorant series and the total intensities for every aromatic series were calculated as sum of the OAV of each one of the compounds assigned to these series. Sensory profile was defined by quantitative descriptive sensory analysis. The fruity, floral and sweet series are the ones most strongly contributing to the aroma of ‘Chardonnay’ wines, independently of nitrogen source added. In general, the fortification of must with nitrogen source enhances the aroma intensity of wines, especially fruity and floral notes. Samples with organic nutrient presented greater aromatic intensity and more floral aromas than samples with inorganic nutrient. According to the results, the fortification of must with organic nitrogen enhanced the aromatic complexity of wines.

Targeted analysis based on high performance liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) has been applied to determine genotypic effect in the phenolic composition of novel white grapes (Vitis vinifera L.). For this purpose, the recently identified white grape genotypes Albillo Dorado and Montonera del Casar were comprehensively profiled and compared to cultivar Airen at two consecutive years (2016 and 2017). Several phenolic compounds were quantified in berry parts and arranged into the following classes: flavonols, flavan-3-ols, hydroxycinnamic acid derivatives and stilbenes. In order to establish the degree of dissimilarity between grape genotypes, data obtained were subjected to statistical analysis included a Principal Component Analysis that provided a good separation according to flavonols, hydroxycinnamic acid derivates and flavan-3-ols from different grape tissues. The approach reported here may serve to clarify the varietal typicity of these new white grape genotypes for producers and consumers, defining their identity and position on the market.

Aim: The aim of the study was to investigate the stilbene composition of grapes and wines of the Vitis vinifera cultivars Tannat, Marselan and Syrah cultivated in Uruguay. The effects of delaying the harvest on stilbene concentrations were determined, and the stability of stilbenes during wine storage was assessed.Methods and results: Stilbene concentrations were determined in the grapes and wines of two vintages (2015 and 2016) and two harvest dates for each cultivar. Vinification was carried out by traditional maceration, and samples of the wines of each vintage were analysed in the period from 3 months after devatting to up to 24 months later. After solid-phase extraction, stilbenes were identified and quantified by HPLC-ESI-MS/MS using a multiple reaction-monitoring approach. In the grape berries, stilbene concentrations were between 1.6 and 7.7 mg/kg, depending on grape cultivar, growing season, and in Syrah, harvest date. In the wines, stilbene concentrations were initially between 0.9 and 5.0 mg/L, being highest in Syrah, lowest in Marselan, and intermediate in Tannat. Stilbene concentrations in the Marselan wines were lower than expected based on stilbene concentrations in the grapes from which they were produced, suggesting poor extraction during winemaking. Total stilbene concentrations remained very stable during the analytical period.Conclusions: Delaying the harvest does not necessarily increase the stilbene content of grapes, but it can do so significantly, as shown for Syrah. For some grape cultivars, such as Marselan, poor extraction of stilbenes during winemaking can limit their concentrations in the resulting wines.Significance and impact of the study: The results of this study show the relevance of grape cultivar, degree of maturity and storage time may have into stilbenes. They provide reference data on the stilbene composition of grapes and wines produced under Uruguayan winegrowing conditions. The high stability of stilbenes during wine storage is relevant for consumers interested in red wine as a source of bioactive compounds. In memory of Prof. Isidro Hermosín-Gutiérrez.

Grapes are considered to be a major source of phenolic compounds as compared with other fruits. To improve the quality of table grapes, some techniques like thinning can be used. In addition, grape cultivars with distinct characteristics are directly linked to its phenolic profile. This study aimed to identify and quantify the phenolic compound profile and yield of the hybrid ‘BRS Vitoria’ seedless table grape under different bunch densities, using a combination of solid-phase extraction (SPE) methodologies and analytical high-performance liquid chromatography-diode array detector with tandem mass spectrometry (HPLC–DAD–ESI-MS/MS). A trial was carried out in 2016, in a commercial vineyard at Marialva, state of Parana (South Brazil). Three weeks after anthesis, the following bunch densities were evaluated: 4.0, 4.5, 5.0, 5.5, and 6 bunches per m2 (corresponding to an estimation of 16, 18, 20, 22, and 24 tons ha−1). The randomized block design was used as a statistical model with each treatment was replicated four times, with one vine per plot. Different characteristics were evaluated at harvest, e.g., soluble solids content (SS), total acidity (TA), maturation index (MI = SS/TA), bunch and berry masses, yield, as well hydroxycinnamic acid derivative (HCAD), anthocyanin, flavonol, and flavan-3-ol contents by HPLC–DAD–ESI-MS/MS analysis. The evaluated bunch densities did not interfere with the physicochemical characteristics of the berries, such as SS and MI. Under the density of 6.0 bunches per m2, the highest yield of 25 tons ha−1 was reached. Under all bunch densities, the phenolic profile presented the same compounds, but at different concentrations. Under a density of 5.0 bunches per m2, the compounds belonging to the anthocyanin and flavonol families were present in high concentrations. In contrast, at the densities of 4.0 and 4.5 bunches per m2, there was a reduction in the flavan-3-ol content. With respect to stilbenes, only the trans-piceid and its cis- isomer were detected. However, their concentrations had no significant influence on the evaluated bunch densities.

Malolactic fermentation (MLF) and aging in oak barrels are two oenological processes which modify the composition and sensory characteristics of the wines. However, there are few studies on the MLF in barrels. This work compares wines in which MLF is carried out in steel tanks and then aged in oak barrels, with wines in which MLF has been carried out in barrels. MLF occurs faster in barrels and while the fundamental structure of the wine is virtually identical, there is less color loss. Some groups of volatile compounds vary significantly depending on whether MLF takes place in tanks prior to aging or in the oak barrels themselves. It was shown that in this latter case, wines were obtained with slightly higher concentrations of methoxy-phenols and approximately double amount of whisky-lactones and furanic compounds.

Due to the current dominance of a few grape varieties in the wine market, the aim of this work was to study the detailed phenolic and volatile composition, chromatic characteristics, and sensorial properties of red wines elaborated with new Vitis vinifera grapes (Moribel and Tinto Fragoso) identified using the High Perfomance Liquid Chromatography-Diode Array Detector-Electrospray Ionization-Tandem Mass Spectrometry (HPLC-DAD-ESI-MS/MS), Gas Chromatography- Mass Spectrometry (GC-MS), CIELab color space, and Napping ® techniques.Tinto Fragoso wine showed higher phenolic content than Moribel, with more anthocyanins, flavonols, and stilbenes. These wines also contained anthocyanin diglucosides not reported for Vitis vinifera wines. The odor activity values of free volatile compounds were calculated to indicate their influence on wine aroma, the fruity aromas of Moribel standing out particularly. The wines studied were positively evaluated by the tasters. Moribel's sensory profile was characterized by red fruit aromas and Tinto Fragoso showed more aromatic intensity and persistence in the mouth.The results obtained from the first characterization of red wines made from novel Vitis vinifera grapes suggest that Moribel and Tinto Fragoso could be appropriate raw materials for the elaboration of quality young red wines. Tinto Fragoso provided wines with sensorial properties different from those of Tempranillo, and could be an alternative to the well known red wines on the market. © 2018 Society of Chemical Industry.

In the present work we evaluate the effects of malolactic fermentation (MLF) on the colour parameters and polyphenolic composition of Petit Verdot red wines. MLF caused a significant decrease in colour intensity in wines, approximately 9%. In line with that, the results showed a decrease in the concentration of anthocyanins (acylated and non-acylated), but an increase of the pyranothocyannins concentration. MLF did not produce important variations on the content of hydroxycinnamic acids derivatives, stilbenes and flavonols. Regarding flavan-3-ols, MLF caused a decrease in monomers, total flavan-3-ols and percentage of galloylation, and an increase on the percentage of prodelphinidins. However, no effect over mean degree of polymerisation was observed. Thus, it is unlikely that these changes may affect the acceptability of wines by consumers.

A frame of reference for the genetic profiles of grapevine cultivars whose cultivation is permitted in Castilla La Mancha (Spain) was established by analyzing 26 nuclear and five chloroplast microsatellite loci. The aim was to validate plant material in such a way as to identify those errors of nomenclature (synonyms and homonyms) that are common in grapevine and that can cause administrative problems and then to search for possible parent-offspring combinations. Results showed no differentiated genetic profile for cv. Verdoncho, which is a synonym of Pardina/Jaen Blanco. The Alarije cv. has a dual legal status, as it coincides genetically with Torrontes. There are also several cases of homonyms affecting the denominations Albillo, Coloraillo, and Moravia Dulce. Each of these embraces a group of different cultivars, some of which have not been described previously, such as Albillo Dorado. Results confirm the origin of cultivars Albillo Dorado, Coloraillo, and Moribel from a cross between Tempranillo and Moravia Dulce, with Moravia Dulce the female parent for all.